If you want to be a professional basketball player and currently play basketball for your school team, it is a good idea to attend basketball camps as well! In terms of schooling, the NBA typically drafts players from Division I schools in the US. A list of Division I schools is compiled here https://blog.prepscholar.com/complete-list-of-division-1-colleges-by-state
Alternatively, if you do not wish to play for a college basketball team, you can also go overseas and play professionally for leagues in China, the Middle East, and Europe before declaring for the draft. In Europe, the Euroleague is the highest tier of professional basketball, but can be quite competitive.
Omar recommends the following next steps: